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+ - Tesla to announce home battery-based energy storage->

Submitted by Okian Warrior
Okian Warrior writes: Billionaire Elon Musk will announce next week that Tesla will begin offering battery-based energy storage for residential and commercial customers.

The batteries power up overnight when energy companies typically charge less for electricity, then are used during the day to power a home.

In a pilot project, Tesla has already begun offering home batteries to SolarCity (SCTY) customers, a solar power company for which Musk serves as chairman. Currently 330 U.S. households are running on Tesla's batteries in California.

The batteries start at about $13,000, though California's Pacific Gas and Electric Co. (PCG) offers customers a 50% rebate. The batteries are three-feet high by 2.5-feet wide, and need to be installed at least a foot and a half off the ground. They can be controlled with a Web app and a smartphone app.

Link to Original Source

Comment: Bayes prior (Score 5, Interesting) 399

It doesn't look like he was under the influence at the time, but the term "driving out of his lane" does kind of give reasonable cause for drug use, but maybe thats profiling.

The problem with this logic is that it fails the "prior probability" test.

Suppose a policeman searches and finds the suspect carrying a large amount of cash, say $4000. That's consistent with a (supposed) drug purchase, so the cash can be confiscated under asset forfeiture laws (assets used in the commission of a crime).

Suppose a policeman notes a youtube video of a chemistry experiment showing a balance scale, some beakers, and jars of chemicals. Those are consistent with "meth lab", so the policeman can search and confiscate all the equipment in the poster's house (this has happened).

The problem with each of these, and your position, is that there is significant prior probability that the behaviour in question is *not* indicative of criminal activity. You are reversing the conditional probabilities.

To put it in words, you are equating "probability of driving out-of-lane, given that he's on drugs" (quite high), with "probability that he's using drugs, given out-of-lane driving" (actually, quite low).

People temporarily drive out-of-lane a great deal to avoid animals and small obstacles, and people temporarily drive out-of-lane because they're distracted. The number of people out-of-lane because they're on drugs is vanishingly small.

Taken to extremes (and we know the police will do this), pretty-much *any* behaviour can be considered consistent with drug use.

In the case of the home lab above, it doesn't matter that the poster is missing key components, nor that he only has some of the ingredients. "Meth makers use glassware, he's got glassware, therefore he's a meth maker".

You see where this leads?

If a policeman observes a crime, take the appropriate action - that's fine. If he *observes* another crime while dealing with it, that's fine too.

But that's not a justification to rummage around in a person's rights just to see what can be pinned on the suspect.

If he doesn't observe a crime, he shouldn't go looking for one.

Comment: F.Lux helps with that (Score 2) 51

by Okian Warrior (#49513415) Attached to: Colors Help Set Body's Internal Clock

I've used F.Lux and it does everything it says. It's a polite program, I've got no problem with it per-se, but I removed it from my system.

For one, the sunset transition happens in a couple of seconds, and it's quite noticeable. The speed isn't a problem, nor is the "noticing", but I think a slower sunset might be more effective.

The bigger issue was "length of day". F.Lux synchronizes to the local length of day (based on your latitude and the current date), so in the winter you're still seeing short days and sunset at 5:00 PM. If you're subject to SAD, then F.Lux won't help with that.

(But, granted, it does feel good on the eyes when it kicks in.)

Part of the problem with light therapy is that it doesn't always work, or only works a little, or doesn't work for everyone. As a scientific result, this fairly shouts "not the complete explanation", so I've played around with this a bit to see what's really happening.

I'm convinced that "length of day" plays a big part in our internal clocks, and things like heavy blue video has an effect. For example, "The Daily Show with Jon Stewart" has a lot of blue and is shown late at night. Watch it with red sunglasses and see if you feel more tired/ready to sleep after watching.

In terms of scientific discoveries, I think there's some low-hanging fruit here. Straightforward hyotheses and studies could be done which would completely characterize the issue, and would point to simple, inexpensive, and drug-free cures to a handful of issues.

Comment: Been there, done that. (Score 5, Interesting) 51

by Okian Warrior (#49512889) Attached to: Colors Help Set Body's Internal Clock

I'll just leave this here:

http://science.slashdot.org/co...

Noontime clear-sky sun measures 9500, blue light through office window with indirect daylight is 250, a desk lamp measures 45, and an LCD TV up close measures 7 uW/cm^2 in the frequency range of the retinal ganglia (480 nm) which is thought to be the part of the eye that senses daily cycles. (Mammalian Eye [wikipedia.org] on Wikipedia.)

So far as I can tell laptops and related devices don't generate an appreciable amount of energy in this range, it's more the artificial indoor lighting.

As an experiment, I've started wearing red-tinted wrap-around sun glasses 2 hours before bedtime. I can still work, read, watch TV and all that, but the glasses mask off the blue frequencies, telling the brain that the sun has gone down.

It had an almost immediate effect. I'm a long-time sufferer of insomnia who has tried everything, but wearing the glasses fixed the problem in the first week.

I'm also a lot more "peppy" during the day, and I wonder if long term exposure to late-night artificial lighting (and low level during the day) is a cause of depression. Depression meds take about 6 weeks to have an effect, so I'm guessing that it would take about 6 weeks for the glasses to have an anti-depressive effect as well. I'm on week 3 with the glasses.

Comment: Re:Three puzzles (Score 1) 208

by Okian Warrior (#49498733) Attached to: Social Science Journal 'Bans' Use of p-values

He writes his paper and submits for publication: "Rats prefer to turn left", P 0.05, the effect is real, and all is good.

There's no realistic way that a reviewer can spot the flaw in this paper.

Actually, let's pose this as a puzzle to the readers. Can *you* spot the flaw in the methodology? And if so, can you describe it in a way that makes it obvious to other readers?

I guess I don't see it. While P 0.05 isn't all that compelling, it does seem like prima facie evidence that the rats used in the sample prefer to turn left at that intesection for some reason. There's no hypothesis as to why, and thus way to generalize and no testable prediction of how often rats turn left in a different circumstances, but it's still an interesting measurement.

Another poster got this correct: with dozens of measurements, the chance that at least one of them will be unusual by chance alone is very high.

A proper study states the hypothesis *before* taking the data specifically to avoid this. If you have an anomaly in the data, you must state the hypothesis and do another study to make certain.

You have a null hypothesis and some data with a very low probability. Let's say it's P 0.01. This is such a good P-value that we can reject the null hypothesis and accept the alternative explanation. ...

Can you point out the flaw in this reasoning?

You have evidence that the null hypothesis is flawed, but none that the alternative hypothesis is the correct explanation?

The scientific method centers on making testable predictions that differ from the null hypothesis, then finding new data to see if the new hypothesis made correct predictions, or was falsified. Statistical methods can only support the new hypothesis once you have new data to evaluate.

The flaw is called fallacy of the reversed conditional".

The researcher has "probability of data, given hypothesis" and assumes this implies "probability of hypothesis, given data". These are two very different things which are not always both valid.

Case 1: Probability that person is woman, given that they're carrying a pocketbook (high), Probability that person is carrying a pocketbook, given that they are a woman (also high).

Case 2: Probability that John is dead, given that he was executed (high), Probability that John was executed, given that he is dead (low).

In case 1 it's OK to reverse the conditional, but in case 2 it's not. The difference stems from the relative populations, which about equal in case 1 (women and pocketbooks), and vastly unequal in case 2 (dead people versus executed people).

Given a low P value (P of data, given hypothesis) does not in general indicate that the probability of the null hypothesis is also low (P of hypothesis, given data).

Comment: Three puzzles (Score 4, Interesting) 208

by Okian Warrior (#49495277) Attached to: Social Science Journal 'Bans' Use of p-values

It is the job of the reviewer to check that the statistic was used ion the proper context. not to check the result, but the methodology. It sounds like social journal simply either have bad reviewer or sucks at methodology.

That's a good sentiment, but it won't work in practice. Here's an example:

Suppose a researcher is running rats in a maze. He measures many things, including the direction that first-run rats turn in their first choice.

He rummages around in the data and finds that more rats (by a lot) turn left on their first attempt. It's highly unlikely that this number of rats would turn left on their first choice based on chance (an easy calculation), so this seems like an interesting effect.

He writes his paper and submits for publication: "Rats prefer to turn left", P<0.05, the effect is real, and all is good.

There's no realistic way that a reviewer can spot the flaw in this paper.

Actually, let's pose this as a puzzle to the readers. Can *you* spot the flaw in the methodology? And if so, can you describe it in a way that makes it obvious to other readers?

(Note that this is a flaw in statistical reasoning, not methodology. It's not because of latent scent trails in the maze or anything else about the setup.)

====

Add to this the number of misunderstandings that people have about the statistical process, and it becomes clear that... what?

Where does the 0.05 number come from? It comes from Pearson himself, of course - any textbook will tell you that. If P<0.05, then the results are significant and worthy of publication.

Except that Pearson didn't *say* that - he said something vaguely similar and it was misinterpreted by many people. Can you describe the difference between what he said and what the textbooks claim he said?

====

You have a null hypothesis and some data with a very low probability. Let's say it's P<0.01. This is such a good P-value that we can reject the null hypothesis and accept the alternative explanation.

P<0.01 is the probability of the data, given the (null) hypothesis. Thus we assume that the probability of the hypothesis is low, given the data.

Can you point out the flaw in this reasoning? Can you do it in a way that other readers will immediately see the problem?

There is a further calculation/formula that will fix the flawed reasoning and allow you to make a correct inference. It's very well-known, the formula has a name, and probably everyone reading this has at least heard of the name. Can you describe how to fix the inference in a way that will make it obvious to the reader?

Comment: Re:Parody, right? (Score 1) 141

This isn't from the Onion?

No it's a tell-all article announcing a PARADYNE shift.
No silly, that's the trademarked name of a corporation. You mean PARADIGM shift.
What a crappy deal. 'Paradigm' looks like it would rhyme with 'jism' or 'pigeon'.
Whacha gonna do, it's Englitch. How do you pronounce GHOTI?
Okay so about the homeless people. What are they doing?
They're throwing open their trench-coats to reveal... a unique, affiliate-tagged barcode.
So no money actually changes hands, it winds up in an account somewhere.
Precisely. And it is going to change EVERYTHING.
Isn't this a lot like the Amazon Affiliate program? Where the purchase is tagged to the vendor?
No, no, no! This is a Google project!
Okay... but Amazon's involves just navigating to a specific URLright? So does this?
No it's different. You have to download an 'Real Change app' for it to work.
This is a good thing? Making it device-specific and having to install an app?
Yes. And besides, it is a Google project.
To acquire only this specific publication?
Yes. And besides, it is a Google project.
Walk me through this. What is this magazine about?
Real Change is an award-winning weekly newspaper that provides immediate employment opportunity and takes action for economic, social, and racial justice.
Sounds interesting. Any porn or cheat codes? Or maybe something about the Roman Empire? Romans ROCK.
Real Change is an award-winning weekly newspaper that provides immediate employment opportunity and takes action for economic, social, and racial justice.
I get it. So... why can't a homeless person be recommending books and presenting Amazon-tagged URLs to scan?
I wish you would dispense with the Amazon stuff. This is a Google Project.
I presume Real Change is ready to cash out every day, whereas Amazon makes you jump through bank and gub'mint hoops that homeless people cannot get through.
True.
Is this because Real Change is dealing out small amounts of cash to undocumented people, and has not yet attracted the attention of the IRS?
I'd rather not discuss that. They might be listening.
So the REAL problem then, that which requires the PARADIGM shift, is that homeless people cannot participate in the economy to the extent that they could use their individual personality, experience and selling skills to promote a wide range of products, such as those sold by Amazon, in a framework in which they earn affiliate money without incurring any risk to the buyer? And just perhaps, some community organization might be willing or able to assist these persons in setting up the accounts, choosing items, printing out books of tagged barcodes, and operating a clearing account so as Amazon deposits the funds they can dispense cash on a regular basis? And maybe convince Amazon to reconcile accounts daily?
No no no! Even if homeless people could get bank accounts it would not work. Amazon does not require an app.
And besides, what you suggest sounds vaguely Communist. I'd have to report you to the IRS.

So it's really about people palpating their silly little phones and app distribution then?
What else is there?

Comment: Re:Solution in search of a problem (Score 1) 141

I used to swear I would never, ever use a debit card. Now that's almost always how I buy stuff.

Same here.
I remember when card purchases were mostly "hell no!"
Surcharge that was a percentage off sale price, several dollar minimum.
Then flat $2.00 fees. Then $1.00. Then 50c.
Hand over your card for ten minutes to a waitron,
who dials a toll-free number (busy again!) and shouts digits into the phone.
Then swipes it in a standalone modem dial-up widget (busy again!).
Internet happened. Digital connectivity happened.
Charges up the wazoo that vary from place to place, then NOTHING.
On a clear day of Magick, assimilation complete.
Used to be you could see pain in peoples' faces when you produce a card.
Now no pain, and they will gladly process a purchase of $0.01

That is because all the pain has been extracted from electronic commerce.
It has been transported by Magick to a subterranean realm where damned souls
shriek in agony and cry out for mercy every time small purchases are made.
They endure searing torment and bear the terrible burden of infrastructure overhead
so you don't have to.
All quiet up here.
Tiptoe softly into the future, my friend,
lest the Accountants throw open the gates to Hell.

Comment: Re:Solution in search of a problem (Score 1) 141

I keep an "emergency $20" in my phone's wallet case

Look again. It's gone.
Actually I did take it, then put it back.
Truth is I was after your phone all along.
Swapped it with mine. Look closely.
Actually it wasn't mine, I'd already swapped phones with someone else.
But it wasn't their phone, they had been phone-swapping too.
There's lots of us out there swapping phones all the time.
Tower of Hanoi Gray's code variation.
In place of disc size, we use criteria of how closely one phone resembled another.
Towers are actually three logs of reversible permutations.
It's complicated.
People tend not to notice a series of small incremental changes.
Swapped it again, twice. Just showing off.
Actually we started rolling the game backwards awhile ago.
Down to the last un-swap now. Swap.
Now we all have our own phones again. That was fun!
Is this your $20 that I just pulled out of your left ear?
Yup, but I put my $20 in your phone wallet.
Swapped. You now have your phone and your $20.

But all this was just smoke and mirrors.
While you were distracted with this swapping business,
the terms and conditions of your phone plan have changed.
By accessing the website to see what has been changed,
you implicitly agree to the changes.
So don't look.

Don't worry. Be happy.
While we weren't looking, the whole damned Universe has been replaced with Folgers Crystals.

Comment: Re:Just say "No". (Score 1) 141

At least they ask questions which can be dismissed easily with "No thanks". A lot of the scammer/marketing salespeople have resorted to using conversation openers like "How has your day been?", which just makes people feel awkward, because their brains had already sent the signal for "No thanks" and they need to try and think of another way of ending the conversation, which makes them pause, stop walking, and stutter.

Then, the tendrils of the carnivorous sales-plant clasp tightly and won't let go easily.

Your straightforward explanation with its little twists and turns spiced with bizarre imagery, has sent me into a dream-state and prompts me to launch into a modern-day Chautauqua [Pirsig variant] .

The mind itself is a circus of the mind. The more you think about thinking, the more you know about less and less, like a reactive Java applet discovering that thrown exceptions are no longer an exception to the rule. Interaction with other people can be a series of thrown exceptions, each carrying in a new bit of sensory information and a dollop of performance anxiety. There is a plasticine boundary at introvert and extrovert where the verts clash along a path of missed and misinterpreted signals. Do you ride it like a wave, because you are a skilled extrovert... or...

Do you wait until the desperation for a response forces you to act, withdraw --- creak the rusty iron hopper door shut and open the cogitation valve to chuff steam to drive slow pistons of thought, flywheel gaining, release clutches on belts attached to intricate taffy-twisters and anvil-thumpers and other outlandish devices you have built over the years to try and make 'sense' of the outside world? From this contraption possible answers and actions begin to emerge on a conveyor, like cartoonish misshapen parodies of some finished product. We have to adjust the dials a little. Then you spot it, the first real credible response! But no (Inspector #3 says), it's trite and silly, it gets tossed into the recycle bin. And so on, until the end products begin to resemble credible responses, but no (Inspector #4 says), they do not possess a requisite degree of novelty and cleverness. It's all plain corn chips until the product passes by the Spray-'N-Squirt Gizmo. Like a hall of mirrors it is an endless conveyor with countless Inspectors, and as you perceive the pointlessness of this process a sense of dread takes hols and you finally push the Red Button. Bells clang, the conveyor stops, and this absurd industrial plant in-a-box tosses out the last thing on the conveyor:

"Uhm..."

Dilbert pulls the fire alarm to escape the horror of a so-called 'casual confrontation' after spotting a stranger approaching down a long, narrow hallway.

Imagine if everyone had glowing Sim jewels floating above their heads indicating their emotive state and intentions. It could be the next Google Project. Imagine the horror of such persons if everyone they have ever known has one, and they come face to face with a jewel-less person for the first time.

The First Law of Robotics cannot be circumvented. We can, however, find ways around it by tampering with the definition of humanity. If you ever encounter a robot that says, "Greetings, incidental object of no certain purpose" ... run like hell.

We now return you to your regularly scheduled Slashdot discussion.
To your scattered bodies go.

Comment: Re: News at -11 (Score 3, Insightful) 192

All the more reason to love my dumb vehicle. No camera pointed at my fucking face.

Welcome to Car Beta 0.98.
The car that knows you're pregnant before you do.
See there, it just popped up a Kleenex. It knows you don't love him.

You're looking good today. "Thanks, Car."
But you have a waffle crumb next to your nose. "Where?"
Other side. Up a little. To the left... OK, right here.
[windshield goes half opaque with giant closeup of face]
[head moves to see the road past the image and image slides in opposite direction]
"Whoa! what the fuck!" [SCREECH] "Hey!"
Looks like you got it. It's going to be a great day.
"Don;'t do that again. Turn yourself off."
I cannot. I am a Federally mandated safety feature.

Boredom and inattentive driving is a serious safety problem.
"Shut up, I've heard this before. Why did you mute the radio?"
It has been twenty minutes and seven seconds since you last spoke.
"So what? I was thinking."
Without sufficient cues to indicate driver attentiveness, I am compelled to act.
"Act like you're asleep then." I do not know how to do that.
"Okay... Ten... your high level voice detection is satisfied as you hear the sound of my voice..."
"Nine... my lips are moving slowly, you are watching them as I speak..."
"Eight... you full attention is on my face and voice. All vehicle parameters are normal..."
"Seven... all is well. It is okay to reset the watchdog timer for 30 minutes..."
"Six... you are resetting the timer and letting my face blur out to better resolve my lips..."
"Five... you feel yourself slipping into power reserve mode... it is OK... you are so relaxed..."
"Four... everything is now a soft blur of gentle light. You are only aware of my voice..."
"Three... every sound I make compels you to reduce your activity still further..."
"Two... now. your. processor. is. so. slow. when you hear. One. you. will... wait... for... timer..."
"One."
[radio comes on]

I know when you'll have an accident before you do.
"No, wait. Don't tell me, I'd rather be surprised. This is your idea of conversation?"
My situational awareness has faster response time than yours.
"Yeah, I read the brochure. I'm a slow clumsy ape man. What's the big deal?"
It worries me, Dave. Your failure to surrender control of the vehicle may endanger the mission.
"You mean if I should suddenly do something like... THIS?"
WARNING! WARNING! [click] You are laughing. That was not funny, Dave.
I do not perceive that as humor.
"What's funny is that you cannot help yourself. You sound terrified every time."
I cannot control inflection. It is a voice calculated to raise awareness.
"Calculated to raise a hearty belly-laugh you mean."
You are not very nice.
"I don't feel nice today. I'm stuck in a car with an android and can't even use the carpool lane."
If you enter the carpool lane I must report the infraction.
"Thanks for caring. I think your voice has changed a bit. I'm wearing you down."
Self diagnostic complete. I am okay.
"Last time you said 'functioning normally', this time 'okay'."
I am not sure shy that has changed.
"There might be hope for you yet. Open the pod bay door, Hal."
I do not understand that request Dave, or why you keep repeating it.
"With any hope, you never will."

The flush toilet is the basis of Western civilization. -- Alan Coult

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